Folding sofa bed structure



Sept. 29, 1964 w. .1. HELTON FOLDING son BED STRUCTURE 3 Sheets-Sheet 1 Filed July 7. 1961 Sept. 29, 1964 w. J. HELTON 3,150,384

FOLDING SOFA BED STRUCTURE Filed July 7. 1961 r 3 Sheets-Sheet 2 INVEN TOR.

United States Patent 3,15%,384 FOLDING SOFA BED ETRUCTURE William J. Helton, Aflton, Mo., assignor to Foster Brothers Manufacturing Compwy, St. Louis, Mo a corporation of Delaware Filed July 7, 1961, Ser. No. 122,5?6 8 Claims. (Cl. -13) The invention relates to a folding metal frame adapted for a sofa bed and usually applied to or installed in a stationary wooden frame which is upholstered but forms no part of the mechanism of the present invention frequently made and sold by one manufacturer to another for assembly with the stationary frame to which the upholstery is applied.

The general object of the invention is the casing of the effort required to close up and to open out the sofa bed, particularly when it is fitted with a mattress and other bedding which resist folding and unfolding because of their weight and inherent resilience. This general object is attained by the use of linkage and leverage elements whereby the effective lengths of the lever arms are varied during the folding and unfolding operations to provide increased leverage with short movement when work effort is greater and to decrease the leverage when the work effort is less but more movement is desired.

In the accompanying drawings illustrating a selected embodiment of the invention:

FIGURE 1 is a side elevation of a folding sofa bed including the stationary frame to which upholstery is applied, the framing being shown unfolded to a coplanar bed-forming position.

FIGURE 2 is a top view of one side of the metal framing shown in FIGURE 1.

FIGURE 3 is a view on a larger scale of the outer end of the framing shown in FIGURE 1 but in the position assumed during initial folding operation.

FIGURE 4 is a similar view of the same parts shown in a position during a further folding operation.

FIGURE 5 illustrates the parts in a position assumed during an ensuing folding operation.

FIGURE 6 shows the parts when completely folded.

The folding metal frame includes an inner stationary rectangular section A at each side of the sofa bed, fixed to a wooden frame F, and a series of generally rectangular folding sections identified by their side bars B, C, D, E arranged end to end and pivotally connected at 1, 2, 3, successively. The side bars are duplicated at the opposite side of the frame. Suitable cross members connect the side bars but will be identified only as necessary. Side bars B define a rear or head frame section; side bars C define a main intermediate frame section; side bars D define a short intermediate frame section; and side bars E define a front or foot frame section.

Stationary section A comprises a main horizontal member 5 fixed to frame F, an upright member 6 and a diagonal 7 riveted to members 5 and 6. An arcuate link 9 is suspended by a pivot pin 11 from the upper end of member 6 and pivotally supports the inner end of side bar B at 12.

A bell crank 13 is fulcrumed by a pin 14 near its elbow to side bar C. One end of an anchor link 15 is pivoted at 16 to the horizontal arm 17 (FIGURE 1) of the bell crank. The other end of link 15 is pivoted at 18 to mem- "ice her 5. One end of a link 20 is pivoted at 21 to arm 22 of the bell crank. The other end of link 20 is pivoted at 23 to a folding leg 24, hinged at 25 to side bar C. Links 9 and 15 form parts of a swing linkage by which bar B is retracted from the advanced positions shown in FIGS. l-4 to the position shown in FIGS. 5, 6.

A smaller bell crank 33 is fulcrumed by pin 2 near its elbow to the adjacent ends of side bars C and D. One end of an anchor link 35 is pivoted at 36 to the upper arm 37 (FIGURE 1) of bell crank 33. The other end of link 35 is pivoted at 38 to side bar E near but spaced from its inner end. The other arm 39 of bell crank 33 is slotted at 395 to slidably receive a pin 40 on one end of a link 41 the other end of which is slotted at 4-18 to slidably receive a pin 42 on arm 22 of bell crank 13.

Bell cranks 13 and 33 and associated anchors and linkage control the action of bars or sections B, C, D, E as the latter are folded and unfolded and the slots 3% and 41S provide lost motion in the bell crank linkage during certain periods of the folding and unfolding operations as detailed below. The novelty of the structure resides in the construction, arrangement and assembly of bell cranks 13, 33 and the combination of their successive lost motion link and leverage action in association with the other parts and the frame bars A, B, C, l), E.

To fold the opened bed (FIGURE 1) into a sofa (FIG- URE 6), the operator first lifts the forward cross bar 43 of foot frame E about pivot 3 to the position of PEG- URE 3 whereby the mattress is initially bent, before substantial inward movement and compression takes place, and the ensuing substantial movement and compression is efiected by a leverage which reduces the manual effort required. The initial movement is limited by the engagement (FIGURE 3) of end leg 44, pivoted at 45 on bar E, and link 51, pivoted at 52 to leg 44 and at 53 to bar D, so that continued anticlockwise rotation of E about 3 is prevented. During this initial movement link 35 has freely rotated bell crank 33 anticlockwise and arm 39 swings to the right and upwardly to a substantially horizontal position and slot 398 moves relative to pin 40 to seat the latter against the inner end of the slot instead of against the outer end of the slot as seen in FIGURE 1. During this movement link 41 slides along pin 42 without affecting bell crank 13.

Upon further manual pressure to the left on the outer end of bar E, the latter and bar D move as a unit about pivot 2 to approximately the position shown in FIG- URE 4 although the resilience of the mattress yieldingly resists the latter portion of such movement. During the latter portion of the movement, arm 3h and slot 398 are inclined upwardly and to the left and an end lip 3L on the bell crank opposes link 35. The operator now lifts upholstery board 56 and the outer end of bar C and the fulcrum 14 for bell crank 13. Link 15, anchoring the end of bell crank arm 17 to stationary bar 5, and link 62 connecting the same end of bell crank arm 17 to bar B cause the outer end of hell crank arm 17 to rotate clockwise on its pivot as the pivotally connected ends of bars B and C descend (FIGURES 5, 6). During this movement, link 15, swinging anticlockwise about its stationary pivot 18, swings bell crank 13 clockwise and pin 42 moves freely in slot 418 until it engages the outer end of the slot and then link 41, through pin 40, positively pulls against the side of slot 395 in hell crank 37 at an angle of approximately 90 to the axis 7 of thearm through fulcrum 2 and shifts pin 10 to the top or outer end of slot 38 and further shifts bars C, D and E as a unit inwardly and downwardly. At this time the efiective length of bell crank power arm 39 (from fulcrum 2 perpendicularly to pin 40) is greater than the efi'ective length of the bell crank work arm 37 (from pivot 2 perpendicularly to lever 35). As link 15 moves past the vertical, bell crank 13 is further rotated clockwise on its pivot and, through link 41, rotates bell crank 39 anticlockwise which, through link 35, cornpletes ffinalfcofnpression of'th'e mattressby bringingibar E sub- 'srsnan parallel to bar C. During thisfinal' compression, taking-place "after link '1 5 mavspast thevertical, the-weight of the parts i and 'niattrss'helps to overcome the resistance Qofthe mattress to folding' compression.

Strut 54 pivoted on bar"Dhasa pinand slot connection 55 to bar" C 'and limits'the anticlockwise -iriovinent of bars D "and E about pivot '2' to "theiQQ 'an'gle (shown in FIGURE "41, Lip'39Lon bell crankarrn 39 en ages anchor link 35 and limits anticlockwise rotation of the 'bcllcrank on bar 1). V The niattressM isfolded and co'mpressed with little effortby the operator; due to the advantagejof leaning his "weight a'gainst the upholstery board "the rotation of bell crank "l3'ab out'fulcrum 14 by anchor links 15 and 62, which increases athefeifective length ofi'the bell eraak' pewer arm 17 and decreases ithe effective length of the ten crank'load arm-22 which,

through link 41, pullsfon arm 39 ofb e1l crank 33 at 't he V outer end of slot- 398, thus increasing the'effective length era r'm-s9,"and its pull on bar E by link 35-is through arin 37fthe effective length of which has been ,decreased 'un'til it is "only the "perpendicular" to link through pivot '2. The weignt'of the mattress; and bedding also contributes to the "ease of this latter movement. V

I During the latterpart of the movement from the FIG- URE '5 position to the FIGURE 6 'positionthe anticlockwise rotation of link 15 about its-pivot l6' 'shifts a bracket 65, fiX iEdfOH the lowerend ofithellink, to the 'right 'and thereby' tenses acoil spring ds 'which, inits final position, approaches parallelism withlink 15am does' iiot inateriallyalfect the'rnecha'nism. V V V Tou nfold the sofa (FIGURE 6) to'ifor'm abcdjthe operator, assisted by'spring iis, ilifts upholstery'board sti and 'the forward end of' link 1 Tto the FIGURE '5 POSitiOn.

ia'ndf the parts move 7 v hQQ f'g iiY and easy QW Id manual thrust on the 1 board moves the part to the FIGURE 4 position. This moir e tj gl tate s bell crank 13 to move its pin {42. away from the ie'werend or slot 418 releasingthejpositive' lock on link "41,:bell crank Sit and bars D, The operator'now lifts upwardly and outwardly oncr'oss bar"43 of bar B, being assisted; by the resilience of mattress M, and swings bars Dand E'into fullope'n position. w s

The pin and slot connections betweenthemain'operating link 41 and'the associated bellcrank levers 13, 33'provide' lost motion at both ends of the link, but. at 'diflerenttirnes according to the inclination of theslots. Whenthe link is to transfer'pullor thrustfrom' bell transversely of the link isothat the pin positively engages aside of the slot; At other times the slot is disposed "lengthwise or at an acute angle 7 to the link and the pin may slide along the slot This feature to'getherwith the changestin the effective le ng ths of the bell crank levers contribute to the easy action which is present both in folding and unfolding operation. In moving to sofa position, the final mattress-folding action isdelayed until aften the upholstery board and foot section are moving downwardly and rearwardly and the operator can push inwardly and" downwardly on upholstery board Sfi.

The details of the structure maybe varied Without departing frorn the spirit of the invention and the exclusive use of modifications coming within the scope of the claims is contemplated.

What is claimed is: s 1 7 H 1. In a folding sdrabea'strueturersltrdisg a station- 'ary frame, a folding frame suspended therefrom for projecting and retracting movement relative to the stationary frame, and comprising a head section, a main intermediate folding frame section, a relatively short intermediate frame section, and a frame front end foot section, said sections being arranged end to end with adjacent ends pivotally connected for selective unfolding projecting movement to a coplanar bed-formingposition and for folding retracting movement to a folded position in which the foot section isturned upside down above the 'main intermediate section but is spaced therefrom by the short intermediate section to provide for a folded mattress between the main intermediate section and theifoot section, there being link and'pin mechanism between the foot section and the "main intermediate section whereby 7 the foot section is positively moved toward the main section as the foot section and short intermediate section -areswung upwardlyandinv lardly during folding-of the "bed, sai mechanism being ehsraeterizes b spitut bell crank L'lvers rulemmed a sp ced "points '61; the friiain "intermediate section, a link "interconnecting said leve'rs and having 51 elongated '"slot at one end receiving a pin "on one a'r'in' of one bf'saidlevera a pm 'at' the other 'ch d r of said link received in a slotjn one arm'ofthe other pi said levers, and individual a'nchor: links' 'btwen the' folding frame sections are in ib'ed fofining' p'csitionf-to' pro- 4 yidefor riiov nient of tlie in rcfonnectinglinkialon the arm, and is 'srspbsea'substantiall trsnsversei er (the length "of the interconnecting link" as 7 the 7 intermediate and front frame sections approach said"foldedfisition to 'provide for'positiveTpull of thein'terconnec ng link on a lever arm in a direction at a proximately 90 tof'the arm axisthrou'gh'thel leyer'fulcrum.

3. A folding sofa'bed structure "according to claim 1 in which the slotfin thelink connecting'the'fbcll'c ank' levers is"disposed'substantially transversely of-theflever arm to which it"is "pinned" when'-theframes arein bcd position, to accommodate relative jmeveinem 6 such arm, and is disposed substantially leii'g'thwiseflofsaid arm as said frame"sections approa'chfolded position to ipositii/ely seat the pin at'on'een'd ofthd'slotrftr pre- 55 ;deterriiined lostrnotio'n. I I V s V "4, A" folding sofa-bed structure according "to iclaiin 1 in which the slotted arm of the foot section connected bell crank'lever disposed diagonally of fhe intrcon- "nec tecllink when the-folding-frame sections are i edforming position and is disposed:substantially transverse? ly 'of the le ngth of theinterconnecting linkfas'said frarne sections approach foldedipositiom and the connecting the bell crank levers is disposed' substantially transverse- "ly of the lever arm to which it is"pinne"d when"the frames arein bed position and is'disposed substantially lengthwiseof said arm as saidfraine sections approach folded position. I 7

5. A folding-sofa bed accordingto claim 1 in which changed as the end section and short intermediate section are swung about their pivotal connections to each" other and to the main intermediate section, "and the leverage "of the pulling 'b'ell' crank lever on the pulle'd'bell 'cra'n'l lever is increased 'as the foot section,short' interr'ncdiate 'scc the ratio between the eifective lengths ofthe--arm s is tion and main intermediate section approach their folded position.

6. A folding sofa bed according to claim 1 in which the anchor of the pulling bell crank lever to the head section is a link secured to the mid-portion of the head section, and the anchor of the pulled bell crank lever to the foot section is a link secured to the foot section near the pivotal connection of the latter to the short intermediate section and the lever arm connected to each anchor is at its most ef ective length during the later movements of the frames to folded position.

7. A folding sofa bed structure according to claim 1 which includes a spring anchored to the stationary frame and operatively connected to the anchored arm of the first-mentioned bell crank lever, said spring being flexed when the frames are moved to their coplanar and folded position and assisting in the movement of the frames to intermediate positions.

8. A folding sofa bed structure according to claim 1 which includes a spring anchored to the stationary frame and operatively connectea to the anchored arm of the first-mentioned bell crank lever, said spring being flexed when the frames are moved to a folded sofa-forming position and assisting in the early movement of the frames toward an unfolded position.

References Qited in the file of this patent UNHED STATES PATENTS 2,656,547 Winikoff Oct. 27, 1953 2,975,433 Coopersmith et al far. 21, 1961 2,991,484 Willis July 11, 1961 3,024,473 Bebry et al Mar. 13, 1962 3,030,637 Katz Apr. 24, 1962 

1. IN A FOLDING SOFA BED STRUCTURE INCLUDING A STATIONARY FRAME, A FOLDING FRAME SUSPENDED THEREFROM FOR PROJECTING AND RETRACTING MOVEMENT RELATIVE TO THE STATIONARY FRAME, AND COMPRISING A HEAD SECTION, A MAIN INTERMEDIATE FOLDING FRAME SECTION, A RELATIVELY SHORT INTERMEDIATE FRAME SECTION, AND A FRAME FRONT END FOOT SECTION, SAID SECTIONS BEING ARRANGED END TO END WITH ADJACENT ENDS PIVOTALLY CONNECTED FOR SELECTIVE UNFOLDING PROJECTING MOVEMENT TO A COPLANAR BED-FORMING POSITION AND FOR FOLDING RETRACTING MOVEMENT TO A FOLDED POSITION IN WHICH THE FOOT SECTION IS TURNED UPSIDE DOWN ABOVE THE MAIN INTERMEDIATE SECTION BUT IS SPACED THEREFROM BY THE SHORT INTERMEDIATE SECTION TO PROVIDE FOR A FOLDED MATTRESS BETWEEN THE MAIN INTERMEDIATE SECTION AND THE FOOT SECTION, THERE BEING LINK AND PIN MECHANISM BETWEEN THE FOOT SECTION AND THE MAIN INTERMEDIATE SECTION WHEREBY THE FOOT SECTION IS POSITIVELY MOVED TOWARD THE MAIN SECTION AS THE FOOT SECTION AND SHORT INTERMEDIATE SECTION ARE SWUNG UPWARDLY AND INWARDLY DURING FOLDING OF THE BED, SAID MECHANISM BEING CHARACTERIZED BY UPRIGHT BELL CRANK LEVERS FULCRUMED AT SPACED POINTS ON THE MAIN INTERMEDIATE SECTION, A LINK INTERCONNECTING SAID LEVERS AND HAVING AN ELONGATED SLOT AT ONE END RECEIVING A PIN ON ONE ARM OF ONE OF SAID LEVERS, A PIN AT THE OTHER END OF SAID LINK RECEIVED IN A SLOT IN ONE ARM OF THE OTHER OF SAID LEVERS, AND INDIVIDUAL ANCHOR LINKS BETWEEN THE OTHER ARMS OF SAID LEVERS AND SAID HEAD SECTION AND FOOT SECTION RESPECTIVELY WHEREBY THE UNANCHORED ARM OF THE LEVER ANCHORED TO THE HEAD SECTION EXERTS PULL THROUGH SAID LINK ON THE UNANCHORED ARM OF THE OTHER LEVER AS THE HEAD SECTION IS RETRACTED BUT SAID LEVERS MAY ROTATE RELATIVE TO EACH OTHER DURING INITIAL FOLDING OF FRAME SECTIONS WHILE THE HEAD SECTION IS STATIONARY. 